Trump has said that he'll nominate someone to replace Whitaker permanently and who'll be subject to a confirmation hearing and vote in the Senate. Until then, however, the non-Senate-confirmed Whitaker is Trump's man at Justice as acting attorney general with full authority, the department says, over all of its operations.

That includes the investigation into whether Trump's campaign may have conspired with the Russians who attacked the 2016 presidential election, the one being run by special counsel Robert Mueller.

Whitaker's appointment not only ejected Sessions, whom Trump never forgave for recusing himself from the Russia matter because he said it was inappropriate to investigate a campaign of which he was part. It also leapfrogged the White House's handpicked interim leader over the Justice Department's actual second-in-command, the Senate-confirmed Deputy Attorney General Rod Rosenstein.

The only person at Justice who Trump may like less than Sessions or Mueller is Rosenstein, who appointed Mueller after Trump fired another top onetime leader within the department: then-FBI Director James Comey.

Whitaker was an outside commentator in the press and on TV before he came back into the government and he warned about Mueller exceeding his authority. He also said "the left is trying to sow this theory" that the Russians interfered with the 2016 election.

That's more than a "theory" now — Mueller's office has charged some two dozen Russians with the interference.

This track record may make things a little awkward in the room between Mueller and Whitaker and it also has prompted a wave of calls from Democrats on Capitol Hill for Whitaker to take himself out of the Russia matter just as Sessions did.

There's been no indication that Whitaker will.

Why are you still here?

Trump and his attorneys have argued that his authority under the Constitution gives him the power to fire anyone in the executive branch for any reason.

That's why they say he simply could not have obstructed justice by firing Comey, and, presumably, the dismissal of Sessions can't be considered improper either.

So why, if Trump considers the Russia investigation "a phony hoax," as he told reporters on Friday, doesn't he just get rid of Mueller too and be done with all this?

That's what Whitaker had discussed doing before he re-joined the government; under one scenario, he said, the attorney general could just stop paying Mueller and his team, or take away other resources they need to work.

Result: The special counsel's office can be smothered from within but with no "Saturday Night Massacre" headlines or transgression of whatever unwritten guardrails may have been put in place for Trump by Senate Majority Leader Mitch McConnell, R-Ky., and outgoing House Speaker Paul Ryan, R-Wis.

McConnell, Ryan and many other leading Republicans on Capitol Hill have gone along with months of political scourging and sandblasting of the Justice Department, the FBI and its leaders — so long, it appeared, as the body count didn't pile up and Mueller especially was spared.

Trump, however, is apparently a big believer in the no-way-to-lose approach, as with his trade restrictions on China: Either Beijing renegotiates to open its markets — a win — or high costs to operate overseas prompt American companies to relocate their operations to the United States — a win, as the president believes.

(Any layoffs, increased near-term costs, unsold soybeans or other interim disruptions are just the price of longer-term victory.)

That may be the strategy that underpins the Whitaker gambit: Put your hand-picked man atop Justice to lean on Mueller — a win. If Mueller and his office don't like it, let him or his team members quit — a win.

(All the fretting and tut-tutting that would result is of no importance, in this view. And what the 2018 elections confirmed for Republican is how much supporters still love to see Trump kicking up a backlash among his favorite patsies in Congress and on TV.)

Besides, as the president said on Friday, he isn't worried about anything under any circumstances, because there's nothing to uncover: "I didn't speak to Russians," he said. "This has nothing to do with Russians. It's a Russia hoax."

Who's in charge here?

What does it all add up to? A Justice Department that is supposed to have been "independent" since Watergate arguably may be less "independent" than any time since then.

Most Republicans hailed Sessions and many of them hailed Whitaker. The Mueller issue, however, does not sit right with a few important players, including Maine Republican Sen. Susan Collins.

"I'm concerned Rod Rosenstein will no longer be overseeing the probe," she wrote. "Special Counsel Mueller must be allowed to complete his work without interference—regardless of who is AG."

Efforts are already underway outside the executive branch to ensure that the proper strictures are put in force. On Friday, a federal appeals court hearing a challenge related to Mueller's authority issued an order for the parties involved to explain "what, if any, effect" the change in leadership at the Justice Department will have for the case.

This kind of legislation has failed to make much progress in the Senate in the past as Republicans leaders sought to assure lawmakers and the public that it wasn't necessary because nothing was going to happen to Mueller.

McConnell said again on Friday that he opposes it, pointing out "I've said before it's not necessary." Pressed on the effort to vote on the bill championed by retiring Sen. Jeff Flake, R-Ariz., and Sen. Chris Coons, D-Del., McConnell said "it's not going to come up because it's not necessary." But that may not stop the bill's supporters from seeking to re-fight this battle.

If Democrats try to attach some protect-Mueller legislation to a federal spending bill that must pass later this year to keep open the government, that could help its chances.

Then again, Trump has said in the past that he's willing to shut down the government in December unless lawmakers agree to fund the wall he wants to build on the southern border.

We've begun what'll likely be two years of brutal trench warfare in which Trump and Democrats — especially the incoming Democratic majority in the House --need each other to be a foil for their respective supporters; the president, in his case, is counting on the high negative perceptions among Republicans of likely incoming House Speaker Nancy Pelosi.

That may mean comity will remain in short supply and Mueller's office, for however much longer it continues its work, may be on its own.